Generic propagation model always have accuracy problems. Without model calibration, it can hardly be used in practice. This article develops a recursive algorithm on radio propagation model calibration for CDMA system...
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ISBN:
(纸本)7505350668
Generic propagation model always have accuracy problems. Without model calibration, it can hardly be used in practice. This article develops a recursive algorithm on radio propagation model calibration for CDMA systems. An evaluation method is introduced and actual drive test results are used to verify the refined model's goodness of fit. From the results it can be seen that the calibration method in this paper is feasible in practice.
A simplified method for the calculation of indoor wireless optical impulse response based on classical recursive algorithm is demonstrated. In the proposed algorithm, the optical characteristics of emitting and receiv...
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ISBN:
(纸本)9781467329972;9781467329965
A simplified method for the calculation of indoor wireless optical impulse response based on classical recursive algorithm is demonstrated. In the proposed algorithm, the optical characteristics of emitting and receiving elements have been used to reduce the complexity of computations while no sacrifice of accuracy is introduced. Theoretical investigation shows that the elementary computations for the third reflection decreases by nearly 50% in comparison with the one that utilizes the classical recursive algorithm, and can obtain a higher reduction percentage when more reflections are to be concerned.
An algorithm is given to reduce computer time for simulation of motion of hinge-connected flexible multibody systems with multiple structural loops. The algorithm is based on using efficient motion variables for elast...
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An algorithm is given to reduce computer time for simulation of motion of hinge-connected flexible multibody systems with multiple structural loops. The algorithm is based on using efficient motion variables for elastic motion and hinge rotation in a recursive formulation for an articulated system of bodies in a tree configuration. This formulation is then used for multiloop systems by cutting the loops at joints and exposing unknown constraint forces. A new development is given of the intertwining of the effects of the constraint forces on the accelerations of the bodies, with constraint force contributions requiring a two-stage update. Explicit expression of the accelerations in terms of the constraint forces leads to a particularly simple form for the evaluation of the latter. Numerical efficiency of the algorithm is shown by examples comparing to a standard, nonrecursive formulation using customary motion variables. Examples include large-angle slewing of a flexible solar sail, flexible multiantenna spacecraft with prescribed motion for internal loads calculation, a whirling chain of flexible bodies with two ends pinned, and a multiloop, flexible multibody mechanism. All the examples demonstrate the relative computational efficiency of the new formulation, with efficiency increasing with increased number of modes per flexible body.
This paper proposes a new approach for global motion estimation using recursive algorithm in the sparsely sampled field, as well as we process parametric estimation in framework of one stage not in proposed pyramid st...
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ISBN:
(纸本)9780769533827
This paper proposes a new approach for global motion estimation using recursive algorithm in the sparsely sampled field, as well as we process parametric estimation in framework of one stage not in proposed pyramid structure. Firstly, we divide the image into blocks and obtain the highest gradient magnitude in each block to form a sparsely sampled field. Then, we derive a new recursive gradient-based algorithm for global motion estimation in sparsely sampled field. The low pass filtering is for eliminating noise of original images before the estimation processes. Finally, we propose one stage framework for the parametric refinement without the proposed hierarchical configuration. The simulation results show the comparisons of performance between our method and others.
Different from the extended Euclidean algorithm which can compute directly only the multiplicative inverse of an element in Zm^＊ and the greatest common divisor of two integers, a recursive algorithm called REESSE is...
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Different from the extended Euclidean algorithm which can compute directly only the multiplicative inverse of an element in Zm^＊ and the greatest common divisor of two integers, a recursive algorithm called REESSE is designed by the authors, which can not only seek directly the multiplicative inverse and the greatest common divisor, but also solve directly a simple congruence for general solutions. This paper presents the definition and the two valuable properties of a simple congruence, analyzes in detail the reduction and recursion process of solving simple congruences, induces the recursive formula for solving simple congruences, and describes formally and implements in C language the recursive algorithm. At last, the paper compares REESSE with the extended Euclidean algorithm in thought, applicability and time complexity.
Aimed at improving power supply reliability, according to the radial pattern of power supply network, reliability analysis of power supply network based on recursive algorithm is put forward in this paper. The power s...
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ISBN:
(纸本)9781479932795
Aimed at improving power supply reliability, according to the radial pattern of power supply network, reliability analysis of power supply network based on recursive algorithm is put forward in this paper. The power supply network is represented by a binary tree, and by means of recursive algorithm in a reverse order, the reliability of sub-feeders are reasonably equivalent by a line to simplify the whole power supply network. Thus, time and space of computation are saved. Finally, a case has been used to illustrate the effectiveness of the method.
Redundancy Allocation Problem (RAP) is one of the most important problems in the field of reliability. This problem is aimed at increasing system reliability under constraints such as cost, weight, etc. This study wor...
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Redundancy Allocation Problem (RAP) is one of the most important problems in the field of reliability. This problem is aimed at increasing system reliability under constraints such as cost, weight, etc. This study works on a system with series-parallel configuration and multi-state components. To draw the problem nearer to the real condition, this study merges this problem with discount levels in purchasing components. For calculating the reliability of sub-systems, a recursive algorithm is used. Because the redundancy allocation problem belongs to NP-hard problems, for optimizing the presented model, a new Genetic algorithm (GA) was used. The algorithm parameters were tuned using Response Surface Methodology (RSM), and an enumeration method was used for the validation of GA. (C) 2020 Sharif University of Technology. All rights reserved.
Based on the research on the optimization model of production/ordering planning problem, this paper presents a new recursive algorithm, taking the sum of the total production cost and holding cost as the minimization ...
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Based on the research on the optimization model of production/ordering planning problem, this paper presents a new recursive algorithm, taking the sum of the total production cost and holding cost as the minimization criteria, to get the correct range of the both variables of stage k production and storage, and finally to get the optimal decision. In the contrast, exsiting normal dynamic programming algorithm could in some events result in a wrong range of the both variables and optimal decision would not be reached.
This paper presents a recursive algorithm for constrained two-dimensional guillotine cutting problems of rectangular items. The algorithm divides a stock plate into a sequence of small rectangular blocks. For the curr...
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This paper presents a recursive algorithm for constrained two-dimensional guillotine cutting problems of rectangular items. The algorithm divides a stock plate into a sequence of small rectangular blocks. For the current block considered, it selects an item, puts it at the left-bottom corner of the block, and determines the direction of the dividing cut that divides the unoccupied region of the block into two smaller blocks for further consideration. The dividing cut is either along the upper edge or along the right edge of the selected item. The upper bound obtained from the unconstrained solution is used to shorten the searching space. The computational results on benchmark problems indicate that the algorithm can improve the solutions, and is faster than other algorithms.
A fast recursive algorithm has been developed to solve for the scattering solution of a large 2-D inhomogeneous body for TM waves. The inhomogeneous body is first divided into N subscattereres. The algorithm uses an a...
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A fast recursive algorithm has been developed to solve for the scattering solution of a large 2-D inhomogeneous body for TM waves. The inhomogeneous body is first divided into N subscattereres. The algorithm uses an aggregate TBAR matrix and translation formulas to solve for the solution of n + 1 subscatterers from the solution for n subscatterers. The computational complexity of the algorithm is of O(NMP2), where NM is the number of unknowns and P is the number of harmonies required in the translation formulas. The memory requirement is proportional to the number of unknowns. The algorithm has been used to solve for the scattering solution of a 10-lambda-diameter two-dimensional scatter with about 12,000 unknowns, taking about 30 s on a CRAY-2 supercomputer.
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